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April 22nd, 1999, 12:51 AM
If any one knows about USB port and how it can be communicated like Serial port, pl reply. If U have source code or any sites for this
it will be great help. Thanks in advance.

Vali
June 13th, 1999, 09:33 PM
USB (Universal Serial Bus) is a new (relatively speaking) bus standard. You do not communicate with this port directly (like serial or parallel ports). Instead, the support for USB is provided through WDM (Windows Driver Model) support under Windows 98 and NT 5(95 OSR1 has this support also but has bugs). As with all WDM based devices, your device must adhere to USB standards (Firmware must be compatible with USB standards) and you talk to your device through a WDM based MINIPORT driver that sits under a USB class driver provided by Microsoft. If you device conforms to a Human Input Device (HID) type or other class types, you must then conform your MINIPORT to the API's prescribed by that class. If you have a special device that does not conform to any predetermined classes of devices, you can write a so called "MONOLITHIC" USB based driver that must still use the USB class driver. Then you can use the IOCTLS/READ/WRITES to talk tothis driver. If you use HID, you can use the API's prescribed in HID.DLL (by Microsoft).

The thing to remember is that you do not talk directly to USB port. This bus is designed to be shared by multiple devices and a single app should never assume exclusive ownership of the port.

Hope this helps. If you eed more info, visit the USB home page on the internet.

Vali.